Testicular torsion

A 17-year-old boy is brought to the emergency department for evaluation of acute right-sided scrotal pain with associated nausea and vomiting. The patient was playing football when he felt sudden pain following a tackle to the abdomen. The patient has tried over the counter analgesia and ice pack placement over the groin without relief of symptoms. He has had similar episodes of pain that self-resolved after 30 minutes. He has no significant past medical history and has received all age-appropriate vaccinations. Temperature is 37.0°C (98.6°F), pulse is 99/min, respirations are 21/min, and blood pressure is 145/80 mmHg. Physical examination reveals an uncomfortable adolescent in significant pain. Examination reveals an edematous and erythematous right scrotum that does not transilluminate. Stroking of the right inner thigh does not result in elevation of the right testis. The pain is worsened with elevation of the scrotum. Which of the following is the most likely etiology of this patient’s clinical condition?